Ice making refrigeration apparatus and the like



c. E. LOWE 3,026,686

ICE MAKING REFRIGERATION APPARATUS AND THE LIKE March 27, 1962 3Sheets-Sheet 1 Filed April 3, 1961 INVENTOR 6Z2: lmre ATTORNEYS March27, 1962 c. E. LOWE 3,026,686

ICE MAKING REFRIGERATION APPARATUS AND THE LIKE Filed April 5, 1961 3Sheets-Sheet 2 INV EN TOR March 27, 1962 c E. LOWE 3,026,686

ICE MAKING REFRIGERATION APPARATUS AND THE LIKE Filed April 3, 1961 3Sheets-Sheet 3 IN VENTOR ATTORNEYS 3,026,686 ICE MAKING REFRIGERATIONAPPARATUS AND THE LIKE Charles E. Lowe, P.0. Box 621, Orlando, Fla.Filed Apr. 3, 1961, Ser. No. 100,138 2 Claims. (Cl. 62-149) The presentinvention relates in general to heat exchange refrigeration systems, andmore particularly to refrigeration systems for ice-making or coolingpurposes which are cycled alternately through a freezing phase and aharvesting or defrosting phase in the operation of the system.

Automatic ice-making apparatus involving reversible cycle refrigerationsystems have gone into wide commercial use. In such systems, ice isproduced during the normal refrigerating or freezing phase of theapparatus when condensed liquid refrigerant is admitted to theevaporator, and the ice is discharged from the evaporator during thedefrosting or harvesting phase when hot gaseeous refrigerant isdelivered directly from the compressor to the evaporator. In suchsystems the operation of the system in reverse phase to the normalrefrigerating phase involves absorption of heat at the condenser by theliquid refrigerant delivered from the evaporator to the condenser whichcontributes to the total refrigeration load imposed on the system. Suchrefrigeration systems have generally been of the heat pump type and haverequired a number of solenoid valves to etfect proper selective controlof intercoupling of the components of the refrigeration system toestablish-the various phases of operation forming the complete cycle ofoperation of the system. Substantial improvement in the economy ofconstruction and operation of such apparatus is eminently desirable.

While the present invention is applicable to liquid chillingapplication, cooled storage room refrigeration and like applications, itwill be described specifically in connection with the automaticproduction of ice to simplify understanding of the construction andoperation of the system.

An object of the present invention is the provision of novel ice makingapparatus having a cycle of operation wherein the apparatus is cycledsuccessively through freezing and thawing phases, which is of economicalconstruction and has a novel mode of operation providing improvedoperating efficiency.

Another object of the present invention is the provision of novelautomatic ice making apparatus which is cycled automatically throughfreezing and harvesting phases,

wherein the harvesting phase duty cycle is substantially reducedproviding greater production of ice during a given period of operation.

Another object of the present invention is the provision of a novelautomatic ice making apparatus operating automatically through freezingand defrosting phases, wherein means are provided for supplying the heatfor defrosting of the ice during the harvesting phase in a mannereffecting a reduction in the total refrigeration load and more efiicientthermal operating characteristics.

Another object of the present invention is the provision of novelautomatic ice making apparatus operating automatically through freezingand harvesting phases wherein the components are intercoupled andcontrolled in a manner effecting a substantial reduction in the numberof valves required and therefore in the cost of production of theapparatus.

Other objects, advantages and capabilities of the present invention willbecome apparent from the following detailed description, taken inconjunction with the accomf ire States Patent panying drawingsillustrating two preferred embodiments of the invention.

In the drawings:

FIGURE 1 is a diagrammatic view of the automatic ice making apparatusconstructed in accordance with one preferred embodiment of the presentinvention wherein a plurality of solenoid valves are provided forcontrolling cycling of the apparatus between alternate phases ofoperation;

FIGURE 2 is a Wiring diagram of a control system for the apparatus ofFIGURE 1;

FIGURE 3 is a diagrammatic view of a second preferred embodiment ofautomatic ice making apparatus constructed in accordance with thepresent invention, employing a 4-way valve for cycling the componentsbetween alternate phases of operation thereof, the valve beingpositioned in this figure to establish the freezing phase of operations;

FIGURE 4 is a diagrammatic view of the apparatus shown in FIGURE 3 withthe valve positioned to establish the harvesting phase thereof; and

FIGURE 5 is a wiring diagram of a form of controlled circuit'for usewith the apparatus of FIGURES 3 and 4.

Referring to the drawings, wherein like reference char acters designatecorresponding parts throughout the several figures and particularly tothe embodiment of the apparatus disclosed in FIGURES 1 and 2 thereof,the automatic ice making apparatus of this embodiment in cludes theusual motor-driven compressor 16 having a high pressure compressordischarge line 11 and a low pressure compressor suction line 12. Thehigh pressure discharge line 11 divides into two branch lines 13 and 14,the branch line 13 leading to the condenser 15 and the branch 14 to theevaporator 16 through the solenoid controlled valve 17. The condenser 15in the embodiment herein shown is of the type formed of an outer tank orshell into which the hot gaseous refrigerant is admitted from the inletbranch 13, having an internal water coil in communication with anexterior source of cool water to Withdraw heat from the hot gaseousrefrigerant admitted to the condenser through heat exchange with the'water in the water coils and condense the refrigerant to the liquidstate. It will be appreciated, however, that any other form of condenserof the many different types now known in the trade may be used insteadof the particular type of condenser herein shown. A condenser outletline 18 leads from a point near the lower end of the condenser 15through the heat exchanger 19 in thermal communication with thecompressor suction line 12, and thence through a capillary tube 20" toinjector tube 21 extending into and opening internally of therefrigerant chamber 22 of the evaporator 16 at a level in the upperregions of the chamber '22.

The evaporator 16 may be of the type disclosed in my copendingapplication, Serial Number 833,411 filed August 13, 1959, in that it isin the general form of a downwardly opening cup or bored cylinder havingradially outwardly and inwardly facing concentric surfaces on which iceis to be formed, between which an annular cylindrical refrigerantchamber 22 is provided through which refrigerant is metered by thecapillary tube 20. Inner and outer spray rings 23 and 24 are disposedadjacent the upper ends of the inner and outer concentric evaporatorsurfaces and are supplied with water from an external source to spraywater downwardly upon the evaporator surfaces to form ice which isfrost-bonded to these surfaces until the harvesting phase begins.

A transfer tube 25 extends upwardly and from a point near the bottom ofthe annular refrigerant chamber 22 of the evaporator 16 to a point nearthe bottom of a refrigerant accumulator 26. The accumulator 26 ispreferaoaacse ably an insulated tank of considerably greater capacitythan the refrigerant chamber 22 of the evaporator. An outlet line 27extends from the upper end of the accumulator 26 through a solenoidcontrolled valve 28 to the T-fitting 29 at the end of the compressorsuction line 12, the line 27 being one branch of the suction line 12.Another branch line 30 extends from the T-fitting 29 through thesolenoid valve 31 to the upper end of the refrigerant chamber 22 of theevaporator 16.

One form of electrical control circuit which may be used to effectautomatic cycling of this apparatus through successive freezing andharvesting phases is illustrated in FlGURE 2, wherein the compressormotor indicated at 32 is in one parallel branch circuit 33 disposedacross the 110 v. supply lines 34-35 With a two pole main power switch36 interposed in the two leads connecting the branch circuit 33 with the110 v. supply lines and a bin switch 37 responsive to the level of icein the usual ice collecting bin interposed in one of the leads to thebranch circuit 33. An additional branch circuit 38 is coupled across thesupply lines 3435 in parallel circuit relation with the branch circuit33 and includes low pressure and high pressure safety switches 39 and 40and a cycling or harvesting switch 41 arranged in series relation in thebranch 38. The cycling switch 41 may be a temperature switch responsiveto the temperature in the zone of the evaporator 16 or a pressureswitch, a time clock switch, or any other well-known type of cyclingswitch, and includes a movable contact which, in the freezing phase,engages a stationary contact as illustrated in broken lines in FIGURE 2,closing the circuit through the coils of solenoid controlled valve 31and through circulating pump motor 43, which supplies pressure for thewater supply to the spray rings 23 and 24, and in the harvesting phaseposition illustrated at solid lines in FIG- URE 2 engages a stationarycontact closing the circuit through the coils of the solenoid controlledvalves 17 and 28 and through an ice crusher motor 42.

In the operation of the embodiment shown in FIG- URES 1 and 2, assumingthat the unit is charged, bin switch 37 and safety switches 39 and 40are all closed, and the main power switch 36 has just been closed, thecompressor motor 32 is energized and a circuit is established throughthe solenoid valve coil 31, the cycling switch 41 being in the brokenline position due to a higher range temperature at the evaporator.Energizing of the coil of the solenoid valve 31 opens the suction branch30 from the evaporator 16 to the compressor suction intake 12, thecirculating pump motor 43 will be energized causing water to be sprayedfrom the spray rings 23, 24, and the coils of the valves 17 and 28 willbe de-energized leaving them in closed condition. Thus, hot gaseousrefrigerant discharged through the high pressure line 11 from thecompressor will be led through the condenser inlet branch 13 to thecondenser 15, where the hot gaseous refrigerant will condense and rejectheat to the water flowing through the interior water coils of thecondenser. The condensed liquid refrigerant will then be conductedthrough the line 18, heat exchanger 19, and capillary tube to theinjector tube 21 to feed the cooled liquid refrigerant into therefrigerant chamber 22 of the evaporator 16. The evaporator of theliquid refrigerant in the evaporator 16, which is under lower pressure,withdraws heat from the water sprayed on the concentric inner and outersurfaces of the evaporator 16, forming two concentric tubes of ice whichare adhered to the evaporator surfaces, the evaporated refrigerant beingdrawn through the branch suction line and compressor suction intake 12to the compressor 10 to again be compressed and discharged to thecondenser.

When the control for the cycling switch 41 senses a selected conditionat the evaporator, for example, a low temperature condition producedupon the formation of a selected amount of ice on the evaporatorsurfaces, the

cycling switch 41 is tripped to assume the solid line positionillustrated in FIGURE 2, wherein the coils of solenoid valves 17 and 28are energized to open these valves, the ice crusher motor 42 isenergized, the circulating pump motor 43 is de-energized, and the coilof solenoid controlled valve 31 is de-energized closing the branchsuction line 30. The high pressure discharge line 11 of the compressor10 is then placed in direct communication with the refrigerant chamberin the evaporator 16 through the branch conduit 14 and valve 17, whichplaces the evaporator refrigerant chamber 22 under high pressure andexpels the liquid refrigerant from the evaporator through the transferline 25 to the accumulator 26, the top of the accumulator 26 now beingin communication with the compressor suction intake 12 through the opensolenoid valve 28 and line 27. In this harvesting phase of the cycle ofoperation of the apparatus, no substantial amount of liquid refrigerantflows through the line 18, heat exchanger 19, and capillary tube 20 asboth the condenser 15 and the refrigerant chamber of the evaporator 16are under high pressure. Since the liquid refrigerant which was in therefrigerant chamber at the conclusion of the freezing cycle is whollyremoved to the accumulator 26 at the beginning of the harvesting phase,the hot gaseous refrigerant is quickly placed in intimate heat exchangerelationship with the concentric cylindrical surfaces bounding therefrigerant chamber to quickly break the frost bond adhering the ice tothe evaporator surfaces and without subjecting the hot gaseousrefrigerant to the heat losses which would occur if the liquidrefrigerant were required to be evaporated from the refrigerant chamber.

When the cycling switch 41 is again tripped in response to discharge ofthe ice from the evaporator 16, the solenoid valve 31 is againde-energized, opening this valve, and the solenoid valves 17 and 28 areclosed, re-establishing the refrigerant paths described in connectionwith the earlier description of the freezing cycyle. Since the openingof the valve 31 at the commencement of the next freezing cyclere-establishes low pressure conditions in the refrigerant chamber of theevaporator 16, the stored liquid refrigerant in the accumulator 26 isthen forced by its own pressure back through the transfer tube 25 to theevaporator to begin further withdrawal of heat from the water sprayed onthe ice forming surfaces of the evaporator 16 without requiring anentirely fresh charge of liquid refrigerant to be supplied from thecondenser 15. Thus, a far more efficient use of the heating and coolingcapacities of the refrigerant is made, resulting in a substantialreduction in the total refrigeration load of the apparatus as comparedwith prior art reversible cycle ice making machines.

Another embodiment of the apparatus is illustrated in FIGURES 3, 4 and 5wherein a solenoid controlled 4- way valve and a check valve areemployed instead of the 3 solenoid controlled valves 17, 28 and 31 ofthe first-described embodiment. In the form shown in FIG- URES 3, 4 and5, the components and communicating lines which correspond to those ofthe first-described embodiment are designated by reference characterswhich are the primes of the reference characters used in the firstembodiment. In this modified form, the branch 14' of the compressor highpressure discharge line 11' leads to an inlet 45 of a four-way valve 46.One outlet 47 of the four-way valve 46 communicates with the branchsuction line 30' extending to the refrigerant chamber 22 of theevaporator 16, another outlet 48 of the four-way valve 46 communicateswith the compressor suction line 12, and a third outlet 49 communicateswith a line 50 extending to the top of the accumulator 26, a check valve51 being interposed in the line 50 which closes on high pressure at thevalve outlet 49 and opens on low pressure at the valve outlet 49. Thefour-way valve 46 includes a valve member 52 which is axially shiftable'along the valve in response to pressure conditions established by apilot valve 53 under control of solenoid coil 54 to communicate thevalve outlet 48 with one of the valve outlets 49 or 47 and leave theother valve outlet in communication with the valve inlet 45.

An electrical control circuit for this modified form of the apparatus isillustrated in FIGURE 5, wherein the cycling of harvesting switch 41selectively assumes either a freezing cycle condition illustrated inbroken lines wherein the circuit is completed through the circulationpump motor 43 or a harvesting cycle position illustrated in solid lineswherein the circuit is established through the crusher motor 42 and thesolenoid coil 54 controlling the four-way valve 46.

In the operation of this modified form, assuming the bin switch 37 andthe safety limit switches 39' and 40 to be closed and the cycling'switch41' to be in the broken line position, upon closing of the main powerswitch 36', the compressor motor '32 and the circulation pump 43 areenergized and the pilot valve solenoid coil 54 is de-energizedpositioning the valve member 52 of the 4-way valve 46 in the positionillustrated in FIG- URE 3 wherein the outlets 47 and 48 are incommunication with each other. In this condition, the hot gaseousrefrigerant discharged through the compressor discharge line 11' flowsthrough the condenser inlet branch 13 and is condensed in the condenser15', and thence passes through the line 18', heat exchanger 19', andcapillary tube 20' to the refrigerant chamber 22' of the evaporator 16where heat exchange occurs with the water sprayed on the surfaces of theevaporator 16' to form ice on these surfaces. The refrigerant chamber16' is in communication with the compressor suction line 12 through theline 30 and 4-way valve outlets 47 and 48. Since the check valve 51 inthe line 50 is in communication through the valve 46 with the valveinlet 45 and compressor discharge branch line 14', the check valve 51 isclosed and the accumulator 26' is effectively out of the refrigerantcircuit. When sufficient ice has formed on the surface of the evaporator16' the cycling switch 41' is shifted to the solid line position,de-energizing the circulating pump motor 43', energizing the crushermotor 42 and energizing the solenoid coil 54 to activate the pilot valve53 to shift the valve member 52 of the fourway valve '46 to the positionshown in FIGURE 4 wherein the valve outlets 48 and 49 are incommunication with each other. Now, the high pressure discharge line 11'and branch 14' are in communication with the refrigerant chamber 22' ofthe evaporator 16' through the four-way valve inlet 45 and outlet 47 andthe line 30', placing the refrigerant chamber 22' under high pressureand expelling the liquid refrigerant therein through the transfer line25' to the accumulator 26', the accumulator outlet line 50 being nowopen through the check valve 51, fourway valve outlets 49 and 48, andthe compressor suction line 12'. When the ice is discharged from theevaporator 16 the cycling switch 41' is again shifted to the broken lineposition, deenergizing the solenoid coil 54 to cause the valve member 52of the four-way valve 46 to be returned to the FIGURE 3 position,wherein suction line 50 from the accumulator is again closed by theclosing of the check valve 51 and the refrigerant chamber of theevaporator 16' is again in direct communication with the compressorsuction line 12'. The stored liquid refrigerant in the accumulator 26'is then transferred by its own pressure back to the evaporator 16' intodirect heat exchange relationship with the Water sprayed on theiceforming surfaces of the evaporator.

While but two preferred examples of the present invention have beenparticularly shown and described, it is apparent that variousmodifications may be made therein within the spirit and scope of theinvention, and it is desired, therefore, that only such limitations beplaced on the invention as are imposed by the prior art and set forth inthe appended claims.

What is claimed is:

1. In ice-making apparatus and the like, a refrigeration system adaptedto be cycled alternately through a freezing phase and a harvesting phaseincluding an evaporator in the form of a downwardly opening, cup-shaped,vertically elongated body having a pair of radially spaced a cylindricalsurfaces concentric with a vertical axis through said evaporator bodyextending substantially throughout the height thereof and defining innerand outer ice-forming surfaces and a closed bottom annular refrigerantchamber therebetween, water spray means adjacent the upper ends of saidinner and outer ice-forming surfaces for spraying water thereon duringthe freezing phase, a compressor having discharge and suction sides, acondenser, an accumulator tank adapted to be disposed out of the fiowpath of refrigerant between the compressor, condenserand evaporatorduring the freezing phase and to receive and store liquid refrigerantfrom the evaporator during the harvesting phase, said accumulator tankhaving a suction conduit connection at the upper end thereof with thesuction side of said compressor for returning vaporized refrigerant tothe compressor only during the harvesting phase, a transfer tubeconnecting the accumulator tank with said refrigerant chamber havingopen ends disposed near the bottom of each, valve means for connectingsaid refrigerant chamber with said suction side of the compressor duringthe freezing phase, conduit means continuously connecting said dischargeside of the compressor with said condenser, conduit means for the flowof condensed liquid refrigerant from said condenser to said refrigerantchamber, valved means for directly applying hot gaseous refrigerantunder pressure from the discharge side of said compressor to saidrefrigerant chamber at the beginning of the harvesting phase to heatsaid ice-forming surfaces and displace liquid refrigerant from saidrefrigerant chamber through said transfer tube to said accumulator tankand disconnecting said refrigerant chamber from said suction side, andvalve means controlling said suction conduit connection of theaccumulator for opening the same only during the harvesting phase, thevalve means controlling said suction conduit connection closing the sameat the beginning of the freezing phase to cause the liquid refrigerantin the accumulator tank to be forced back through the transfer tube intosaid refrigerant chamber.

2. In ice-making apparatus and the like, a refrigeration system adaptedto be cycled alternately through a freezing phase and a harvesting phaseincluding an evaporator in the form of a downwardly opening, cup'shaped,vertically elongated body having a pair of radially spaced cylindricalsurfaces concentric with a vertical axis through said evaporator bodyextending substantially throughout the height thereof and defining innerand outer ice-forming surfaces and a closed bottom annular refrigerantchamber therebetween, water spray means adjacent the upper ends of saidinner and outer ice-forming surfaces for spraying water thereon duringthe freezing phase, a compressor having discharge and suction sides, acondenser, a heat exchanger, a four-way valve having connections withthe suction side of said compressor and with said refrigerant chamber,said compressor, condenser and evaporator forming a series flow circuitfor refrigerant during said freezing phase, an accumulator tank adaptedto be disposed out of said series flow circuit during said freezingphase and being adapted to receive and store liquid refrigerant fromsaid evaporator during said harvesting phase, said accumulator tankhaving a valved suction conduit connection from the top thereof to saidfour-way valve, a liquid transfer tube connecting the accumulator tankwith said refrigerant chamber having open ends disposed near the bottomof each, a branched conduit connected to the discharge side of saidcompressor having a first branch connected with said condenser and asecond branch connected with said fourway valve means, said four-wayvalve means including means for connecting said refrigerant chamber withsaid suction side of the compressor through said heat exchanger duringthe freezing phase and concurrently dis- 7 connecting said refrigerantchamber from said second branch of the branched conduit connected to thedischarge side of the compressor, conduit means for the flow ofcondensed liquid refrigerant from said condenser from said heatexchanger to said refrigerant chamber, said four-way valve means furtherincluding means for connecting said refrigerant chamber With the secondbranch of said branched conduit connected to the discharge side of thecompressor for directly applying hot gaseous refrigerant under pressurefrom the compressor to said refrigerant chamber at the beginning of theharvesting phase to heat said ice-forming surfaces, said fourway valvemeans including means disconnecting said refrigerant chamber from saidsuction side of the compressor during the harvesting phase andconnecting said suction conduit connection of said accumulator tank withsaid suction side for withdrawing only gaseous refrigerant from saidaccumulator tank to said compressor, said accumulator tank being "inopen communication through said transfer tube with said refrigerantchamber during the harvesting cycle to receive liquid refrigerant fromsaid refrigerant chamber responsive to pressures produced in saidrefrigerant chamber, and means closing said suction conduit connectionat the beginning of the freezing phase to cause the liquid refrigerantin the accumulator tank to be forced back through the transfer tube intosaid-refrigerant chamber.

References Cited "in the file of this patent UNITED STATES PATENTS

